81426433 has 4 divisors (see below), whose sum is σ = 88828848. Its totient is φ = 74024020.

The previous prime is 81426427. The next prime is 81426437. The reversal of 81426433 is 33462418.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81426433 is a prime.

It is a super-2 number, since 2×81426433² = 13260527982206978, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 81426395 and 81426404.

It is not an unprimeable number, because it can be changed into a prime (81426437) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3701191 + ... + 3701212.

It is an arithmetic number, because the mean of its divisors is an integer number (22207212).

Almost surely, 2^81426433 is an apocalyptic number.

It is an amenable number.

81426433 is a deficient number, since it is larger than the sum of its proper divisors (7402415).

81426433 is a wasteful number, since it uses less digits than its factorization.

81426433 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7402414.

The product of its digits is 13824, while the sum is 31.

The square root of 81426433 is about 9023.6596234565. The cubic root of 81426433 is about 433.4328299473.

The spelling of 81426433 in words is "eighty-one million, four hundred twenty-six thousand, four hundred thirty-three".